Aspects of the present invention are directed to a circuit breaker apparatus and, more particularly, to a circuit breaker apparatus having a field configurable rating plug installed therein.
A circuit breaker apparatus may be employed in various commercial, residential and industrial applications to interrupt current and/or voltage in circuits to which they are attached. Generally, a protection level provided by the current/voltage interruption capability of a circuit breaker apparatus is defined by an electronic trip unit (ETU), which is installed therein and which is a device that may control various operational aspects of the circuit breaker apparatus, such as a current versus time trip response.
The operational parameters of the ETU and the circuit breaker, which define the protection level of the circuit breaker and the trip response characteristics thereof, are set on the rating plugs of the ETU which may be factory set. That is, circuit boards of the rating plugs are physically cut for a particular circuit breaker apparatus configuration. Once this configuration is set, it usually cannot be conveniently changed in the field. If the operational parameters of the ETU and the circuit breaker apparatus need to be modified, then, the factory set rating plugs generally need to be replaced.
Some rating plugs, however, may be field-modified by an actuation of various switches found on-board the rating plugs. These field-modifiable rating plugs have multiple settings that can be set or reset by an operator thereof who would be responsible for mechanically manipulating the switches. Unfortunately, the operator in these cases must physically go to the breaker and manually change settings. Also, such operator modifications may additionally lead to a possibility of intermittent switch positions, which can cause a nuisance trip or an un-intended protection setting to be placed in effect.